Semi-trailer trucks are frequently used to transport cargo of various kinds. A typical semi-trailer truck includes a tractor unit and an elongated, wheeled trailer which is articulately coupled to the tractor unit. The trailer typically includes a pair of rear doors which are opened to facilitate loading and unloading of cargo into and from, respectively, the interior of the trailer.
Cargo is typically loaded into the trailer of a semi-trailer truck at a manufacturing facility or a warehouse or other distribution facility and then transported to an unloading destination which may have one or more loading docks. Loading and unloading of heavy and/or large cargo is often particularly problematic when conventional loading and unloading methods and techniques are used. Loading of cargo into the trailer may be facilitated using a temporary ramp, one end of which is typically supported by the rear end of the trailer and the other end of which typically rests on the ground. The cargo must then be pushed, pulled or rolled up the ramp into the trailer. In some applications, an elevated platform or lifting equipment such as a forklift may be used to load cargo into the trailer.
In the event of lack of space or an insufficient number of loading docks at the unloading destination, truckers may be required to wait in line for unloading of the cargo, potentially retarding the progress of business. Moreover, delivery of cargo to its destination (e.g., a retail store or a fast food establishment) may require that the truck be parked in the parking lot of the establishment, a flimsy ramp be extended from the rear of the trailer and a dolly used to transport the cargo from the trailer, down the ramp and into the establishment. In some applications, a forklift may be used to unload the cargo from the trailer. In other applications, the cargo may be placed on a heavy rack which is rolled off the trailer using a lift gate. However, these techniques are attended by dangers such as the risk of the unloading personnel inadvertently falling off the trailer, ramp or lifting equipment or dropping and breaking the cargo. Moreover, the ramp may have a tendency to slip off of the trailer. The ramp may be sloped at a steep angle, necessitating that the loading and unloading personnel overcome the pull of gravity to transport the cargo up or down the ramp. Under circumstances in which the cargo is to be loaded or unloaded at a residence or remote location, for example, forklifts or other lifting equipment may not be available for the purpose.
Accordingly, there is an established need for an improved vehicle trailer system that solves at least one of the aforementioned problems, and facilitates safe and expedited loading and/or unloading of the cargo, particularly in small spaces.